相关论文: Long-Distance Contributions to the $\Lambda_b\righ…
We present the new analysis of the semileptonic B decays in the framework of the relativistic quark model based on the quasipotential approach. Decays both to heavy D^{(*)} and light \pi(\rho) mesons are considered. All relativistic effects…
We calculate the form factors for weak decays of $B_{(s)}$ and $D_{(s)}$ mesons to light pseudoscalar and vector mesons within a relativistic dispersion approach based on the constituent quark picture. This approach gives the form factors…
We present the results of a lattice computation of the form factors for B^0 ->pi^- l^+nu_l decays near zero-recoil. These results will allow a determination of the CKM matrix element |Vub| when measurements of the differential decay rate…
We construct an effective Lagrangian describing the interaction of soft pions and kaons with mesons containing a heavy quark and light degrees of freedom in an orbital $p$ wave. The formalism is easily extended to heavy mesons and baryons…
We investigate the rare decay $\Lambda_b \to \Lambda \gamma$ which receives both short and long distance contributions. We estimate the long distance contributions and find them very small. The form factors are obtained from $\Lambda_c \to…
The form factors parameterizing the B_c semileptonic matrix elements can be related to a few invariant functions if the decoupling of the spin of the heavy quarks in B_c and in the mesons produced in the semileptonic decays is exploited. We…
With data collected in a dedicated energy scan from 2.3864 up to 3.0800 GeV, the BESIII collaboration provides the first complete energy-dependent measurements of the $\Lambda$ electromagnetic form factors in the time-like region. By…
A relation among the form factors of $<D \mid A_\mu \mid D^*>$ at $q^2 \to 0$ is derived. It is verified to lowest order in both the $1/m_c$ expansion and the expansion in number of derivatives using the effective lagrangian that…
We present a QCD sum rule calculation of the spin-symmetry violating universal function $\chi_2(v\cdot v')$, which appears at order $1/m_Q$ in the heavy quark expansion of meson form factors. This function vanishes in the standard…
We investigate rare semileptonic \bar B -> \bar K^* l^+ l^- decays, providing a comprehensive treatment of theoretical uncertainties in the low-q^2 region as needed for interpreting current and future LHCb and B-factory data in terms of the…
We present a systematic discussion of Lambda_b -> Lambda transition form factors in the framework of soft-collinear effective theory (SCET). The universal soft form factor, which enters the symmetry relations in the limit of large recoil…
The Relativistic Flux Tube model is used to calculate of the Isgur-Wise functions describing the exclusive semileptonic decays of $\bar{B}$ and $\bar{B}_{s}$ mesons. The light quark mass dependence is investigated and the predicted…
Several lattice collaborations performing simulations with 2+1 light dynamical quarks have experienced difficulties in fitting their data with standard Nf=3 chiral expansions at next-to-leading order, yielding low values of the quark…
We derive the the effective lagrangian that describes the interactions among vector, axial-vector mesons and pseudoscalars starting from the extended chiral quark model (ECQM). The results for the low-energy constants of this effective…
At order ${\mathcal O}(\alpha G_{\mathrm F})$, the amplitudes for the decays $K\to\pi \ell^+\ell^-$ involve a form factor given by the matrix element of the time-ordered product of the electromagnetic current with the four-quark operators…
The radiative decay $\Sigma_Q^* \rightarrow \Lambda_Q\gamma$ can have both magnetic dipole (M1) and electric quadrupole (E2) components. In the heavy quark limit $M_Q\rightarrow\infty$ the transition arises from the spin of the light…
We employ the QCD sum rule method to study the semileptonic weak decay of the single bottom baryon $\Omega_{b}^{*}$ with spin $\frac{3}{2}$ into the single charmed baryon $\Omega_{c}^{*}$ with spin $\frac{3}{2}$, corresponding to a…
In order to obtain information about the Standard Model from exclusive hadronic two-body B-decays, we have to quantify non-perturbative QCD effects. Approaches based on the factorization of mass singularities into hadronic distribution…
We determine chiral loop corrections to the B meson decay amplitudes to positive and negative parity charmed mesons within a framework which combines heavy quark and chiral symmetries. Then we investigate the impact of the lowest-lying…
We apply the light-cone QCD sum rules with chiral currents to compute transition form factors of the semileptonic decay of the charmed and bottom scalar mesons $D/B$ to $a_{0}(980)l^{+}\nu_{l}$ $(l=e$, $\mu)$, where the scalar meson…